Imaging diagnosis--Dorsal mediastinal T-cell lymphoma in an alpaca.

A 14-year-old male alpaca had refractory pleural effusion. The cause of the effusion was not apparent either radiographically or sonographically, or following a pleural fluid cytologic examination. Using computed tomographic (CT) examination, a dorsal paravertebral mass was identified and similar masses were found in the cranial mediastinum, retroperitoneal space, and adjacent to the hepatic entry of the portal vein. The histopathologic diagnosis was multicentric T-cell lymphoma. CT examination may prove to be a valuable imaging modality in the localization and staging of neoplasia in new world camelids.